The best initial cervical cancer screening tool for younger women is still the traditional Pap smear. However, a large Danish study has found that for older women (age 40 and older), a test for human papillomavirus (HPV) is a much more effective way to screen for potential cancer.
The reason, report researchers in the November 1 issue of Cancer Research, is that HPV infection is both frequent and transient in younger women, and they would often test positive for HPV when no actual risk of cervical cancer existed. But, in older women, HPV infection is rarer and more persistent, putting a woman at substantial risk for the disease before changes in cervical cells, detected by Pap smears, are obvious.
An HPV test detects certain human papillomaviruses (HPVs), depending on the test. Certain types of sexually transmitted HPVs can cause cervical cancer. Persistent infection with one or more of about a dozen a “high-risk” HPV types is an important factor in nearly all cases of cervical cancer. The development of HPV-induced cervical cancer is a slow process that generally takes many years. During this development phase, pre-cancerous cells can be detected by annual or semi-annual cervical cytology screening or “Pap test.” More recently a method for detecting the DNA of high-risk HPVs has been added to the range of clinical options for cervical cancer screening. The US FDA has approved this “hybrid-capture” test, marketed by Digene, for use as an alternative or adjunct to Pap testing.
In gynecology, the Papanikolaou test (also called Pap smear, Pap test, cervical smear, or smear test) is a medical screening method for detecting infectious, premalignant, and malignant processes in the ectocervix, endocervix and endometrium. The pre-cancerous changes (called dysplasias or cervical or endocervical intraepithelial neoplasia) are usually caused by sexually-transmitted human papillomaviruses (HPVs). The test aims to detect and prevent the progression of HPV-induced cervical cancer and other abnormalities in the female genital tract by sampling cells from the outer opening of the cervix (latin for “neck”) of the uterus and the endocervix. The sampling technique changed very little since its invention by Georgios Papanikolaou (1883?1962) to detect cyclic hormonal changes in vaginal cells in the early 20th century until the development of liquid based cell monolayer technology. The test remains a highly effective, widely used method for early detection of cervical cancer and pre-cancer.